#include <fstream>
#include <vector>

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int DIM = 100005;
int n, m, x, y;
vector<int> v[DIM];
bool visited[DIM];

void dfs(int node) {
    visited[node] = true;
    for (int i = 0; i < v[node].size(); i++)
        if (!visited[v[node][i]])
            dfs(v[node][i]);
}

int main() {
    fin >> n >> m;
    for (int i = 1; i <= m; i++) {
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }

    int conCompCnt = 0;
    for (int i = 1; i <= n; i++) {
        if (!visited[i]) {
            conCompCnt++;
            dfs(i);
        }
    }

    fout << conCompCnt;

    return 0;
}